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- Bannbers, Elin, 1984-, et al.
(författare)
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Prefrontal activity during response inhibition decreases over time in the postpartum period
- 2013
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Ingår i: Behavioural Brain Research. - : Elsevier BV. - 0166-4328 .- 1872-7549. ; 241, s. 132-138
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Tidskriftsartikel (refereegranskat)abstract
- The postpartum period is characterized by complex hormonal changes, but human imaging studies in the postpartum period have thus far predominantly focused on the neural correlates of maternal behavior or postpartum depression, whereas longitudinal studies on neural correlates of cognitive function across the postpartum period in healthy women are lacking. The aim of this study was to longitudinally examine response inhibition, as a measure of executive function, during the postpartum period and its neural correlates in healthy postpartum women and non-postpartum controls. Thirteen healthy postpartum women underwent event-related functional magnetic resonance imaging while performing a Go/NoGo task. The first assessment was made within 48 h of delivery, and the second at 4-7 weeks postpartum. In addition, 13 healthy women examined twice during the menstrual cycle were included as non-postpartum controls. In postpartum women region of interest analyses revealed task-related decreased activations in the right inferior frontal gyrus, right anterior cingulate, and bilateral precentral gyri at the late postpartum assessment. Generally, postpartum women displayed lower activity during response inhibition in the bilateral inferior frontal gyri and precentral gyri compared to non-postpartum controls. No differences in performance on the Go/NoGo task were found between time-points or between groups. In conclusion, this study has discovered that brain activity in prefrontal areas during a response inhibition task decreases throughout the course of the first postpartum weeks and is lower than in non-postpartum controls. Further studies on the normal adaptive brain activity changes that occur during the postpartum period are warranted. (C) 2012 Elsevier B.V. All rights reserved.
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| 4. |
- Bannbers, Elin, et al.
(författare)
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The effect of premenstrual dysphoric disorder and menstrual cycle phase on brain activity during response inhibition
- 2012
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Ingår i: Journal of Affective Disorders. - : Elsevier BV. - 0165-0327 .- 1573-2517. ; 142:1-3, s. 347-350
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Premenstrual dysphoric disorder (PMDD) has generally not been associated with impulsive behavior. However, some studies suggest that women with PMDD have higher impulsivity scores than healthy controls and that brain activity during response inhibition may vary across the menstrual cycle. Therefore, our aim was to unravel potentially important cognitive aspects of PMDD by investigating brain activity during response inhibition in women with PMDD and healthy controls in relation to menstrual cycle phase.METHODS:Fourteen PMDD patients and 13 healthy controls performed a Go/NoGo task to measure brain activity during response inhibition by use of event-related functional magnetic resonance imaging.RESULTS:Women with PMDD displayed decreased activity during both menstrual cycle phases compared to healthy controls in several task-related parietal areas. A significant group by phase interactions was found in the left insula, driven by enhanced activity among healthy controls in the follicular phase and by enhanced insula activity during the luteal phase among PMDD patients.LIMITATIONS:The limitations of the present study are the relatively limited sample size, the relatively small number of NoGo trials and the lack of a baseline contrast for the NoGo trials.CONCLUSIONS:During response inhibition women with PMDD have reduced activity in areas associated with attention and motor function which is unrelated to menstrual cycle phase. Insular cortex activity, involved in both affective and cognitive processing, was significantly activated during the luteal phase among PMDD women. These findings are relevant for the understanding of how ovarian steroids influence mood symptoms in women.
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| 5. |
- Benedict, Christian, et al.
(författare)
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Acute Sleep Deprivation Enhances the Brain's Response to Hedonic Food Stimuli : An fMRI Study
- 2012
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 97:3, s. E443-447
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Tidskriftsartikel (refereegranskat)abstract
- Context:There is growing recognition that a large number of individuals living in Western society are chronically sleep deprived. Sleep deprivation is associated with an increase in food consumption and appetite. However, the brain regions that are most susceptible to sleep deprivation-induced changes when processing food stimuli are unknown.Objective:Our objective was to examine brain activation after sleep and sleep deprivation in response to images of food.Intervention:Twelve normal-weight male subjects were examined on two sessions in a counterbalanced fashion: after one night of total sleep deprivation and one night of sleep. On the morning after either total sleep deprivation or sleep, neural activation was measured by functional magnetic resonance imaging in a block design alternating between high- and low-calorie food items. Hunger ratings and morning fasting plasma glucose concentrations were assessed before the scan, as were appetite ratings in response to food images after the scan.Main Outcome Measures:Compared with sleep, total sleep deprivation was associated with an increased activation in the right anterior cingulate cortex in response to food images, independent of calorie content and prescan hunger ratings. Relative to the postsleep condition, in the total sleep deprivation condition, the activation in the anterior cingulate cortex evoked by foods correlated positively with postscan subjective appetite ratings. Self-reported hunger after the nocturnal vigil was enhanced, but importantly, no change in fasting plasma glucose concentration was found.Conclusions:These results provide evidence that acute sleep loss enhances hedonic stimulus processing in the brain underlying the drive to consume food, independent of plasma glucose levels. These findings highlight a potentially important mechanism contributing to the growing levels of obesity in Western society.
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| 6. |
- Comasco, Erika, et al.
(författare)
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Emotional fronto-cingulate cortex activation and brain derived neurotrophic factor polymorphism in premenstrual dysphoric disorder
- 2014
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Ingår i: Human Brain Mapping. - : Wiley. - 1065-9471 .- 1097-0193. ; 35:9, s. 4450-4458
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Tidskriftsartikel (refereegranskat)abstract
- Premenstrual dysphoric disorder (PMDD) is the prototypical sex-specific disorder in which symptom onset and offset require a particular hormonal milieu and for which there is moderate heritability. The present study investigated brain emotion processing in PMDD and healthy controls, as well as functional polymorphisms in two candidate genes for PMDD, the serotonin transporter (5-HTT) and brain derived neurotrophic factor (BDNF). The 5-HTT linked polymorphic region (5-HTTLPR) and BDNF Val66Met polymorphisms were genotyped in 31 patients with PMDD and 31 healthy controls. A subset of 16 patients and 15 controls participated in two functional magnetic resonance imaging-sessions performing an emotion processing task; once in the mid-follicular, and once in the late luteal phase which corresponds with maximum severity of mood symptoms. Genotypes were not directly associated with PMDD. A main effect of group was found in the whole brain analysis, with patients having lower activation of the pre-genual anterior cingulate and ventro-medial prefrontal cortex, independent of menstrual cycle phase. Post-hoc functional ROI analyses in the fronto-cingulate cluster showed no effect of 5-HTTLPR genotype but a genotype-by-group-by-phase interaction effect of BDNF Val66Met. Women with PMDD who were carriers of the Met-allele had lower fronto-cingulate cortex activation in the luteal phase compared to Met-allele carrying controls. The results provide suggestive evidence of impaired emotion-induced fronto-cingulate cortex activation in PMDD patients. Although limited by a small sample, the potential influence of BDNF Val66Met in PMDD is in line with preclinical findings. Hum Brain Mapp, 2014.
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| 9. |
- Frick, Andreas, et al.
(författare)
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Classifying social anxiety disorder using multivoxel pattern analyses of brain function and structure
- 2014
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Ingår i: Behavioural Brain Research. - : Elsevier BV. - 0166-4328 .- 1872-7549. ; 75:9, s. 358S-358S
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Tidskriftsartikel (refereegranskat)abstract
- Functional neuroimaging of social anxiety disorder (SAD) support altered neural activation to threat-provoking stimuli focally in the fear network, while structural differences are distributed over the temporal and frontal cortices as well as limbic structures. Previous neuroimaging studies have investigated the brain at the voxel level using mass-univariate methods which do not enable detection of more complex patterns of activity and structural alterations that may separate SAD from healthy individuals. Support vector machine (SVM) is a supervised machine learning method that capitalizes on brain activation and structural patterns to classify individuals. The aim of this study was to investigate if it is possible to discriminate SAD patients (n = 14) from healthy controls (n = 12) using SVM based on (1) functional magnetic resonance imaging during fearful face processing and (2) regional gray matter volume. Whole brain and region of interest (fear network) SVM analyses were performed for both modalities. For functional scans, significant classifications were obtained both at whole brain level and when restricting the analysis to the fear network while gray matter SVM analyses correctly classified participants only when using the whole brain search volume. These results support that SAD is characterized by aberrant neural activation to affective stimuli in the fear network, while disorder-related alterations in regional gray matter volume are more diffusely distributed over the whole brain. SVM may thus be useful for identifying imaging biomarkers of SAD.
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| 10. |
- Frick, Andreas, et al.
(författare)
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Enlargement of visual processing regions in social anxiety disorder is related to symptom severity
- 2014
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Ingår i: Neuroscience Letters. - : Elsevier BV. - 0304-3940 .- 1872-7972. ; 583, s. 114-119
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Tidskriftsartikel (refereegranskat)abstract
- Social anxiety disorder (SAD) is associated with altered brain function and structure, but most structural studies include small samples and findings are mixed. This study compared regional gray matter volume between 48 SAD patients and 29 healthy controls (HC) as well as the relationship between volume and symptom severity. Structural magnetic resonance images from SAD patients and HC were evaluated using standard voxel-based morphometry (VBM) processing in the SPM8 software package. Social anxiety symptom severity was rated in SAD patients by a clinician using the Liebowitz Social Anxiety Scale (LSAS). SAD patients had greater regional gray matter volume in the lingual gyrus and lateral occipital cortex than the controls, and within the SAD group a positive correlation was found between symptom severity and regional gray matter volume in the lingual gyrus and the retrosplenial cortex. These findings replicate and extend earlier reports of enlarged visual processing areas in SAD. Increased gray matter volume in regions involved in visual processing and self-consciousness could underlie, or be the result of, abnormal emotional information processing and self-focused attention previously demonstrated in patients with SAD.
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